JP6300921B2 - Air conditioning ventilator - Google Patents

Description

  The present invention relates to an air conditioning ventilator.

  The air-conditioning ventilator has a built-in total heat exchanger that exchanges heat between supply air and exhaust, and an air-conditioning coil for heating and cooling immediately after the total heat exchanger in the air path on the supply side Built in. The air-conditioning ventilator exchanges heat between the supply air and exhaust air with a total heat exchanger, and heats or cools the air supply after heat exchange with an air-conditioning coil, and humidifies or dehumidifies indoor air and outdoor air. Ventilate by simultaneous supply and exhaust.

  In the humidity control ventilator disclosed in Patent Document 1, heat exchange is performed between the supply air supplied from the outdoor to the indoor and the exhaust discharged from the indoor to the outdoor, and the outdoor temperature is equal to or higher than a predetermined reference temperature. At the time, the dehumidifying function is executed, and when the outdoor temperature is lower than a predetermined reference temperature, the humidifying function is executed.

  Further, the ventilator disclosed in Patent Document 2 satisfies the required humidification amount in which the safety factor is added to the absolute humidity difference between the indoor and outdoor air with respect to the indoor absolute humidity obtained from the preset indoor temperature and indoor humidity. Therefore, there is provided means for controlling the heating amount of the air conditioning coil in accordance with the outside air temperature humidity so that the absolute humidity of the supply air supplied from the ventilation air conditioner to the room is equal to or higher than a reference value.

  In the dehumidification control of the heat exchange ventilator, control is performed to execute the dehumidification function at a fixed value of 100% or less of the capacity of the air conditioning coil at all times regardless of the outside air humidity within the range where the outside air temperature can be dehumidified. The air temperature after heat exchange is calculated based on the measurement results of the target temperature set with the remote controller, the room temperature, and the outdoor temperature, so that the capacity of the air conditioning coil changes only from the temperature difference between the calculated value and the target temperature. Since the control for executing the dehumidifying function is well known and both continue the dehumidifying operation regardless of the outside air humidity, even when the dehumidifying load due to the absolute humidity difference between the indoor and outdoor air is small, the blowing temperature of the ventilation air conditioner is too low, There were problems such as condensation on the surface of the blowout grill.

  As an example of performing local temperature and humidity control indoors, in the air conditioner disclosed in Patent Document 3, a target temperature and a target humidity are set, and an indoor blower, a cooling dehumidifier, and a reheater are set based on the target temperature and target humidity. A control device is provided that can control and control the temperature and humidity in the air-conditioned area.

  In addition, the air conditioner disclosed in Patent Document 4 determines an operation mode based on the detected indoor temperature and outside air temperature during dehumidifying operation, and corrects according to the difference between the indoor humidity and the indoor set humidity. The compressor is controlled by giving the amount to the compressor rotation speed, and the outdoor fan is controlled by giving the correction amount corresponding to the detected room temperature and the set temperature difference to the outdoor fan rotation speed. In some cases, the correction is alternately performed at predetermined time intervals and stable control is performed in the vicinity of the set temperature and humidity.

  In the dehumidification control of the air conditioner capable of reheat dehumidification disclosed in Patent Document 5, a difference ΔX between the humidity or absolute humidity in the air-conditioned room and the target humidity or absolute humidity is calculated, and the target evaporation temperature is calculated based on ΔX. Set and perform dehumidification control to control the rotation speed of the compressor based on the target evaporation temperature, and at the same time calculate the difference ΔTr between the detected temperature in the air-conditioned room and the target temperature, and based on ΔTr, the expansion valve of the indoor coil In some cases, temperature control is performed to control the opening degree.

JP 2000-97478 A International Publication No. 2012/077201 JP 2006-29598 A Japanese Patent Laid-Open No. 2001-41541 JP 2012-17889 A

  When temperature and humidity control is performed without ventilation with outside air, as disclosed in Patent Documents 3, 4, and 5, the indoor temperature and the target temperature are compared, or the indoor humidity and the target humidity are compared. A control method for performing a dehumidifying operation and a control method for adjusting the room temperature and the room humidity to target values based on the detected room temperature and room humidity are employed. However, the invention disclosed in Patent Documents 3, 4, and 5 cannot be applied to an air-conditioning ventilator because it is not a control that performs a dehumidifying operation with an air-conditioning coil while performing heat exchange ventilation between indoor and outdoor intake and exhaust flows.

  In addition, as disclosed in Patent Document 2, as conventional control of an air-conditioning ventilator that heats and humidifies or dehumidifies supply air after heat exchange with an air-conditioning coil while exchanging heat between indoor and outdoor intake and exhaust flows, When the air supply is heated by an air conditioning coil and humidified by a humidifier, the absolute air blown out from the air conditioning ventilator must be satisfied so that the required humidification amount with the safety factor added to the absolute humidity difference between the indoor and outdoor air is satisfied. The heating capacity of the air conditioning coil is controlled based on the outside air temperature humidity map so that the humidity is equal to or higher than a preset indoor target absolute humidity. However, Patent Document 2 does not disclose means for controlling the cooling capacity of the air conditioning coil in accordance with the outside air temperature and humidity when the ventilation air conditioner is in a cooling operation.

  As conventional control in the case of dehumidifying operation with an air conditioning coil while performing heat exchange ventilation between indoor and outdoor intake and exhaust flows, as disclosed in Patent Document 1, the outdoor temperature is compared with the target temperature, and the outdoor temperature is set as the target. There is a control to perform a dehumidifying operation above the temperature and to execute a humidifying function when the outside air temperature is lower than the target temperature.

  In the control of Patent Document 1, when the indoor temperature is low and the outdoor temperature is lower than a predetermined reference temperature, for example, when the outdoor temperature is low and the humidity is high humidity, the air conditioning coil does not perform the dehumidifying operation. There has been a problem that indoor humidity is increased more than necessary by air exchanged between the air and the exhaust.

  In addition, as a known control, in an air-conditioning ventilator that dehumidifies the air supply after heat exchange with an air-conditioning coil while exchanging heat between indoor and outdoor intake and exhaust flows, the outside air temperature is within the dehumidifying operation range regardless of the outside air humidity. The cooling capacity of the air conditioning coil is always fixed to 100% or less, and the target cooling capacity of the air conditioning coil is determined from the temperature difference between the preset target temperature and the calculated value. Dehumidifying operation control is performed. The air conditioning coil thermo-on / off judgment uses only the outside air temperature and does not include the outside air humidity in the judgment formula. Compares the target temperature set by the remote controller with the air conditioning coil inlet temperature, and the air conditioning coil inlet temperature is the target temperature. If it is lower than that, the cooling operation is not performed by the air conditioning coil, and the air heat-exchanged by the heat exchanger is supplied to the room as it is.

  For example, when the indoor temperature / humidity is 26 ° C. and 50% and the outside air temperature humidity is 22 ° C. and 70%, that is, the indoor temperature is 26 ° C. and the absolute humidity is 0.0105 kg / kg (DA), and the outdoor temperature is 22 ° C. When the absolute humidity is 0.0116 kg / kg (DA) and the temperature exchange efficiency of the heat exchanger is 70% and the humidity exchange efficiency is 73%, the air after the heat exchange is 24.8 ° C. and the absolute humidity is 0 0108 kg / kg (DA).

  In this case, the absolute humidity after heat exchange is higher than the absolute humidity in the room, and if ventilation with simultaneous supply and exhaust continues, the absolute humidity in the room rises, causing discomfort and cooling of other air conditioners installed indoors. The load may be increased, and the entire air conditioning system may not lead to energy saving operation.

  In this way, when the air conditioning coil dehumidifies the air supply after heat exchange while heat exchange ventilation between indoor and outdoor air supply / exhaust air flow, controlling the air conditioning coil based only on the outside air temperature makes the indoor humidity comfortable. In some cases, the range could not be maintained.

  The present invention has been made in view of the above, and based on the outside air temperature and the outside air humidity, the air conditioning coil is provided with a cooling capacity value at which the absolute humidity of the air supplied to the room is equal to or lower than a preset target absolute humidity. It aims at obtaining the air-conditioning ventilator which operates.

  In order to solve the above-described problems and achieve the object, the present invention exhausts indoor air to the outside of the room and adjusts the outside air to a preset indoor target temperature and indoor target absolute humidity and supplies the air indoors. An air-conditioning ventilator having a casing having an air supply air passage connecting the outdoor air inlet and the indoor air outlet, an exhaust air passage connecting the indoor air inlet and the outdoor air outlet, and the air supply air passage. It is installed on the exhaust air channel and an air supply blower that sucks outside air from the outdoor air inlet and supplies the air from the indoor air outlet to the room, sucks indoor air from the indoor air inlet, and Installed on the downstream side of the heat exchanger in the supply air path, and the heat exchanger that is installed between the supply air duct and the exhaust air path and that exchanges heat between the supply air and the exhaust Multi-stage cooling capacity for outside air after heat exchange The absolute humidity of the supply air is less than or equal to the target absolute humidity for each combination of the air conditioning coil, the outside air temperature sensor that measures the outside air temperature and relative humidity, and the outside air temperature and relative humidity. The reference data that determines the cooling capacity based on the dehumidifying load corresponding to the absolute humidity difference between the inside and outside of the room is stored, and the cooling of the air conditioning coil is performed based on the measurement result of the outside air humidity sensor and the reference data during the cooling operation. And a control unit for determining a capability value.

  The air-conditioning ventilator according to the present invention is capable of operating an air-conditioning coil with a cooling capacity value at which the absolute humidity of the air supplied to the room is equal to or lower than a preset indoor target absolute humidity based on the outside air temperature and the outside air humidity. There is an effect.

FIG. 1 is a cross-sectional view of an air-conditioning ventilator according to an embodiment of the present invention. FIG. 2 is a longitudinal sectional view of the air-conditioning ventilator according to the embodiment of the present invention. FIG. 3 is a cross-sectional view of the air-conditioning ventilator during bypass ventilation. FIG. 4 is a diagram showing an example of an outside air temperature / humidity map in which the capacity value of the air conditioning coil of the ventilation air conditioner controlled according to the measured value of the outside air temperature / humidity sensor is divided into zones according to the outside air temperature and the outside air humidity. FIG. 5 is a diagram showing an outdoor temperature / humidity map in which the preset indoor target absolute humidity is set to a high value. FIG. 6 is a flowchart showing a flow of control of the air conditioning coil during operation in the cooling mode or the dehumidifying mode. FIG. 7 is a flowchart showing a flow of the operation of the blowing limiter function.

  Embodiments of an air-conditioning ventilator according to the present invention will be described below in detail with reference to the drawings. Note that the present invention is not limited to the embodiments.

Embodiment.
FIG. 1 is a cross-sectional view of an air-conditioning ventilator according to an embodiment of the present invention. FIG. 2 is a longitudinal sectional view of the air-conditioning ventilator according to the embodiment of the present invention. The air-conditioning ventilator 50 is provided with a set of an outdoor suction port 14 and an outdoor air outlet 13 on the outdoor side of the casing 5 constituting the box of the device, and the indoor air inlet 10 and the indoor air outlet 12 on the indoor side. There is one set. In the casing 5, the outdoor air inlet 14 and the indoor air outlet 12 are connected to each other, and the air supply passage for supplying outdoor air into the room is communicated with the indoor air inlet 10 and the outdoor air outlet 13. An exhaust passage for exhausting indoor air to the outside is provided independently over the entire route. A heat exchanger 3 for exchanging heat between the supply air and the exhaust air is installed between the supply passage and the exhaust passage.

  The air supply air 22 in the air supply passage passes through the outdoor intake ventilation passage 15 from the outdoor air inlet 14, passes through the air supply passage 31 of the heat exchanger 3, passes through the air supply ventilation passage 17, and passes through the air supply blower 6. Then, it passes through the humidification air passage section 27 provided with the air conditioning coil 7 and the humidifier 8 provided on the downstream side of the air supply blower 6, and blows out from the indoor side air outlet 12 to the outdoor side. In FIG. 1, the air supply 22 is indicated by a solid line arrow.

  In addition, the exhaust flow 18 passes from the indoor suction port 10 through the indoor suction air passage 9, through the exhaust passage 30 of the heat exchanger 3, through the exhaust blower 1, through the exhaust ventilation passage 2, and on the outdoor side. It blows out from the blower outlet 13. In FIG. 1, the exhaust flow 18 is indicated by a broken-line arrow.

  The exhaust passage is provided with a bypass air passage 21 for preventing the exhaust flow 18 from passing through the heat exchanger 3. In addition, the exhaust path is provided with a damper 4 that switches the air path through which the exhaust flow 18 passes to either the exhaust path 30 or the bypass air path 21 of the heat exchanger 3.

Heat exchanger 3 by opening the maintenance cover 16 is removable from the Ke pacing 5 from the horizontal direction, are incorporated two in series. The exhaust passage 30 and the supply passage 31 intersect at an angle in the heat exchanger 3 inside the casing 5. The heat exchanger 3 is disposed between the supply air passage and the exhaust air passage and continuously exchanges heat between the supply air and the exhaust air, using outdoor air as supply air, and indoor air as exhaust air. Heat exchange can be performed.

  A bypass air passage 21 is formed between the back side surface of the heat exchanger 3 on the back side and the inner surface of the casing 5 when viewed from the maintenance cover 16 side. When the bypass air passage 21 is opened by opening and closing the damper 4, the indoor air can be exhausted to the outside by the exhaust blower 1 without passing through the heat exchanger 3. As a result, ventilation without heat exchange between the supply air and the exhaust, so-called bypass ventilation can be performed.

  FIG. 3 is a cross-sectional view of the air-conditioning ventilator during bypass ventilation. During the bypass ventilation, the exhaust stream 18 passes through the bypass air passage 21 and does not pass through the heat exchanger 3. Therefore, no heat exchange is performed between the supply air flow 22 and the exhaust flow 18.

  The air-conditioning ventilator 50 includes a control unit 23 that controls the ventilation operation and a remote controller 25 that receives an operation mode switching operation and the like. In addition to a central processing unit (CPU) 23a, a random access memory (RAM) 23b, and the like, the control unit 23 includes a non-volatile storage device 23c that stores an outside air temperature and humidity map, which will be described later, in a non-volatile manner. The nonvolatile storage device 23c is, for example, an NVRAM (non-volatile random access memory).

The refrigerant pipe 26 of the air conditioning coil 7 is disposed so as to protrude from the casing 5 constituting the box of the air conditioning ventilator 50. The air conditioning coil 7 is connected to a heat source unit 24 having a compressor, a heat source side heat exchanger, a blower, and throttle means by a refrigerant pipe 26 to constitute a refrigeration cycle, and is operated by a remote controller 25 for cooling operation and heating. Switching to operation, in other words, switching between dehumidifying operation and humidifying operation is possible. Further, as will be described later, the operating capacity of the air conditioning coil 7 can be switched in multiple stages. The air-conditioning coil 7, the liquid pipe temperature sensor 11 and the gas pipe temperature sensor 19 as a refrigerant temperature sensor for measuring the temperature of the refrigerant flowing through the air-conditioning coil 7 during cooling operation and heating operation is provided, the air-conditioning ventilator 50 An electronic expansion valve 20 is provided as a refrigerant flow rate adjusting means for adjusting the flow rate of the refrigerant flowing through the air conditioning coil 7 .

  Moreover, the humidification air path part 27 by which the air-conditioning coil 7 and the humidifier 8 are arrange | positioned is comprised by the humidification air path upper part 33 and the humidification air path lower part 32 which are divided | segmented and arrange | positioned in the up-down direction shown in FIG. . The humidification air path upper part 33 is formed in the form which covers the air conditioning coil 7 and the humidifier 8 with foaming resin. The lower part of the humidified air passage 32 is provided with a foaming resin drain pan, and is formed to have a structure in which a plastic material is simultaneously formed on the water receiving surface of the drain pan to prevent the foamed resin material from being submerged. The humidified air passage upper portion 33 and the humidified air passage lower portion 32 have a fitting structure in the vertical direction, and integrally form the humidified air passage portion 27.

  An outdoor air flow passage 15 between the outdoor air inlet 14 and the heat exchanger 3 is provided with an outside air temperature / humidity sensor 28 that measures the temperature and relative humidity of the outside air. An indoor temperature / humidity sensor 29 that measures the temperature and relative humidity of the indoor air is provided in the air supply ventilation path 17 between the indoor suction port 10 and the heat exchanger 3. The control unit 23 determines the cooling capacity of the air conditioning coil 7 based on temperature and humidity information that is a measurement result of the outside air temperature and humidity sensor 28 and the indoor temperature and humidity sensor 29.

  The outside air that has passed through the heat exchanger 3 is cooled and dehumidified by the air conditioning coil 7, passes through the humidifier 8 that stops water supply, and is supplied into the room through the indoor outlet 12. At that time, the dehumidifying amount and the blowing temperature are adjusted by the cooling capacity amount of the air conditioning coil 7.

  When the supply air is blown directly into the room from the air-conditioning ventilator 50, if the temperature of the blown air falls below the dew point of the indoor environment, the blowout grill attached to the ceiling surface is cooled and the blowout grille surface is condensed. It is necessary to adjust the temperature so that it does not fall below the dew point.

  FIG. 4 is a diagram showing an example of an outside air temperature / humidity map in which the capacity value of the air conditioning coil of the ventilation air conditioner controlled according to the measured value of the outside air temperature / humidity sensor is divided into zones according to the outside air temperature and the outside air humidity. This outside air temperature / humidity map calculates the outside air absolute humidity from the preset indoor target absolute humidity and the temperature / humidity measured value of the outside air temperature / humidity sensor 28, and satisfies the dehumidification load due to the difference between the indoor and outdoor absolute humidity. When the absolute humidity of the air heat-exchanged by the heat exchanger 3 is lower than the indoor target absolute humidity, the refrigerant is not passed through the air conditioning coil 7 and the heat exchanger 3 is used. The capacity of the air-conditioning coil 7 is controlled so as to satisfy the dehumidifying load with the collected humidity.

  Specifically, the outdoor temperature / humidity map shown in FIG. 4 is based on a preset reference value of the indoor absolute humidity, for example, an absolute humidity of 0.0105 kg / kg (DA) at 26 ° C. and a relative humidity of 50%. Then, using the total heat exchange efficiency of the heat exchanger 3 measured in advance, the temperature and the absolute humidity of the supply air after the total heat exchange in the heat exchanger 3 are set to the outside air temperature and the outside air, which are the temperatures of the outside air. It is calculated for each combination of outside air humidity which is air humidity.

  The outdoor temperature / humidity map shown in FIG. 4 compares the absolute humidity of the supply air after heat exchange with the indoor target absolute humidity, and when the absolute humidity of the supply air after heat exchange is higher than the indoor target absolute humidity, It is determined that the dehumidifying load is not satisfied, and the opening degree of the electronic expansion valve 20 is set to the open side so as to increase the cooling capacity based on the cooling capacity characteristics of the air conditioning coil 7 obtained by measurement in advance. By gradually changing the opening of the electronic expansion valve 20 to the throttle side according to the dehumidifying load so as to satisfy the dehumidifying load due to the absolute humidity difference, and plotting the capacity value of the air conditioning coil 7 that satisfies the dehumidifying load. Has been created.

  The outside air temperature / humidity map determines that the dehumidifying load is satisfied when the absolute humidity of the supply air after heat exchange is lower than the indoor target absolute humidity, so that no refrigerant flows through the air conditioning coil 7. Is also obtained by obtaining and plotting a value that can satisfy the dehumidifying load by the humidity recovery amount of the heat exchanger 3.

  The outside air temperature / humidity map will be described in detail. A region (5) where the outside air temperature is less than T1 and a region (6) where the outside air temperature exceeds T2 are the cooling operation prohibition range of the air conditioning coil 7, and T1 ≦ outside air Regions (1) to (4) where temperature ≦ T2 are regions where the air conditioning coil 7 can be cooled. In the area (5), the outside air temperature is high, and it is outside the operable range in the specifications of the heat source unit 24, so the cooling operation of the air conditioning coil 7 is prohibited. On the other hand, in the area (6), since the outside air temperature is low and it is not necessary to perform the cooling operation by the air conditioning coil 7, the cooling operation is prohibited.

  The boundary α1 is a set of plots in which the following formula (1) is established when the air conditioning coil 7 is operated at a cooling capacity of 100%. The boundary α2 is an aggregate of plots in which the following expression (1) is established when the air conditioning coil 7 is operated at a cooling capacity of 75%. The boundary α3 is a set of plots in which the following formula (1) is established when the air conditioning coil 7 is operated at a cooling capacity of 50%.

  [Absolute humidity of air blown from air-conditioning ventilator] = [Indoor target absolute humidity] Formula (1)

  In FIG. 4, since the outside air temperature / humidity map is created by setting the outside air relative humidity in increments of 5% and the outside air temperature in steps of 5 degrees, the boundary α2 and the boundary α3 overlap at an outside air temperature of 30 degrees. When the outside air temperature / humidity map is created in finer increments of temperature and humidity, the boundary α2 and the boundary α3 do not overlap each other and continue to the high humidity side in the outdoor air temperature / humidity map.

  In the area (1), the outdoor outdoor absolute humidity is higher than the preset indoor target absolute humidity reference value, and the dehumidification load obtained from the absolute humidity difference between the indoor and outdoor air cannot be satisfied with the air heat-exchanged by the heat exchanger 3. It shows an outside air temperature and humidity range, and is an aggregate of plots when the dehumidifying operation is performed so that the cooling capacity of the air conditioning coil 7 is 100% at the maximum. In other words, the area (1) indicates an outside air temperature / humidity range in which the outdoor air absolute humidity is higher than a preset indoor target absolute humidity reference value and the following equation (2) is established.

  [Absolute humidity of outside air after heat exchange] ≧ [preset indoor target absolute humidity reference value] + correction value a (2)

  In the area (1), in the actual operation state, the liquid pipe temperature sensor 11 and the gas pipe temperature sensor 19 of the air conditioning coil 7 aim at the first target superheat degree of the refrigeration cycle in which the cooling capacity of the air conditioning coil 7 becomes 100%. The superheat degree of the refrigeration cycle is calculated by the control unit 23, and the dehumidifying operation is performed while the opening degree of the electronic expansion valve 20 is adjusted in the opening direction so that the first target superheat degree≈the actual superheat degree. Here, the correction value a is a first humidity correction value for preventing the humidity of the supply air from becoming lower than the indoor target absolute humidity. By satisfying the above equation (2), the absolute humidity of the outdoor air after heat exchange becomes a value smaller than the indoor target absolute humidity by a correction value a or more, so the supply air humidity becomes lower than the indoor target absolute humidity. Can be prevented.

  In the area (2), the outdoor air absolute humidity is higher than the preset indoor target absolute humidity reference value, and the dehumidification load obtained from the absolute humidity difference between the indoor and outdoor air is satisfied in the supply air heat-exchanged by the heat exchanger 3. Although the outside temperature humidity range which cannot be performed is shown, it is a plot aggregate in which the above formula (1) is established when the cooling capacity of the air conditioning coil 7 is operated with a cooling capacity of 75% or more and less than 100%. In other words, the region (2) indicates an outside air temperature / humidity range in which the absolute humidity of the supply air that has undergone total heat exchange in the heat exchanger 3 satisfies the following formula (3).

  [Absolute humidity of outside air after heat exchange] ≧ [preset indoor target absolute humidity reference value] + correction value b (3)

In the region (2), aiming at the second target superheat degree of the refrigeration cycle in which the cooling capacity of the air conditioning coil 7 is, for example, 75% so that the above formula (1) is established, the liquid pipe temperature sensor 11 of the air conditioning coil 7 and The superheat degree of the refrigeration cycle in the actual operation state is calculated by the control unit 23 from the gas pipe temperature sensor 19, and the opening degree of the electronic expansion valve 20 is set in the region (1) so that the second target superheat degree≈the actual superheat degree. Perform dehumidifying operation while adjusting the throttle. Here, the correction value b is a second humidity correction value for preventing the humidity of the supply air from becoming lower than the indoor target absolute humidity. By satisfying the above expression (3), the absolute humidity of the outdoor air after heat exchange becomes a value smaller than the indoor target absolute humidity by a correction value b or more, so the humidity of the supply air is lower than the indoor target absolute humidity. Can be prevented.

  In the area (3), the outdoor air absolute humidity is higher than the preset indoor target absolute humidity reference value, and the dehumidification load obtained from the absolute humidity difference between the indoor and outdoor air is satisfactory when the heat exchange is performed by the heat exchanger 3. Although the outside air temperature / humidity range is shown, it is a plot aggregate in which the above formula (1) is established when the cooling capacity of the air conditioning coil 7 is operated with a cooling capacity of 50% or more and less than 75%. In other words, the region (3) indicates an outside air temperature / humidity range in which the absolute humidity of the supply air that has undergone total heat exchange in the heat exchanger 3 satisfies the following formula (4).

  [Absolute humidity of outside air after heat exchange] ≧ [preset indoor target absolute humidity reference value] + correction value c (4)

In the region (3), aiming at the third target superheat degree of the refrigeration cycle in which the cooling capacity of the air conditioning coil 7 is, for example, 50% so that the above formula (1) is established, The superheat degree of the refrigeration cycle in the actual operation state is calculated by the control unit 23 from the gas pipe temperature sensor 19, and the opening degree of the electronic expansion valve 20 is set in the region (2) so that the third target superheat degree≈the actual superheat degree. Perform dehumidifying operation while adjusting the throttle. Here, the correction value c is a third humidity correction value for preventing the humidity of the supply air from becoming lower than the indoor target absolute humidity. By satisfying the above equation (4), the absolute humidity of the outdoor air after heat exchange is a value that is smaller than the indoor target absolute humidity by a correction value c or more, so the humidity of the supply air is lower than the indoor target absolute humidity. Can be prevented.

  In addition, since it becomes easy to produce an error in the dehumidification amount by the air conditioning coil 7 as the operation is performed in a state where the cooling capacity of the air conditioning coil 7 is high, the correction value a, the correction value b, and the correction value c are generally There is a relationship of correction value a> correction value b> correction value c.

  Region (4) shows the outside air temperature / humidity range when the absolute humidity of the outside air that has been completely heat-exchanged by the heat exchanger 3 is lower than the indoor target absolute humidity reference value, and the refrigerant flows through the air conditioning coil 7. This is a range in which the air-blowing operation is performed, that is, a range in which the air conditioning coil 7 is thermo-off and the air-blowing operation is performed. However, when the following formula (5) is satisfied, the temperature of the outside air is sufficiently lower than the indoor target temperature, so that the outside air is supplied into the room without performing heat exchange with the heat exchanger 3. When the following formula (5) is not satisfied, heat exchange is performed.

  [Measured temperature value of outside air temperature / humidity sensor 28] ≦ [indoor target temperature] −correction value d (5)

  Here, the correction value d is a temperature correction value for preventing the temperature of the supply air from becoming lower than the indoor target temperature.

  The control unit 23 stores the outside air temperature and humidity map in a nonvolatile storage device, and controls the refrigerant flow rate of the air conditioning coil 7 based on the outside air temperature and humidity map during operation in the cooling mode and during operation in the dehumidifying mode. I do.

FIG. 5 is a diagram showing an outdoor temperature / humidity map in which the preset indoor target absolute humidity is set to a high value. During cooling operation, for example, if the outside air is 35 ° C. and the relative humidity is 40%, that is, the absolute humidity is 0.0141 kg / kg (DA), and the indoor target absolute humidity is higher than the indoor target absolute humidity reference value, dehumidifying load is determined from the absolute humidity difference is reduced, the boundary alpha 1～Arufa3 moved to the outside air temperature high-temperature side of the outdoor air temperature and humidity map, so that the spread outside temperature and humidity ranges for the thermo-off region (4) . The control unit 23 stores the outdoor air temperature / humidity map so as to switch based on preset indoor target temperature and indoor target absolute humidity high, medium and low. That is, for each combination of the indoor target temperature and the indoor target absolute humidity, the outdoor storage temperature 23c is stored in the non-volatile storage device 23c, and the indoor target temperature and the indoor target absolute humidity are used based on which combination is selected. The controller 23 may switch the outside air temperature / humidity map.

  Further, in the nonvolatile storage device 23c, based on whether the operation mode of the air-conditioning ventilator 50 is the heating mode or the cooling mode, the air-conditioning coil 7 is provided in accordance with, for example, the outside air temperature and humidity disclosed in Patent Document 2. An outside air temperature / humidity map to be humidified by controlling the heating amount is stored, and the control unit 23 switches the outside air temperature / humidity map based on a preset combination of the indoor target temperature and the indoor target absolute humidity. Also good. That is, the controller 23 stores a plurality of outdoor temperature / humidity maps for operation in the cooling mode and outdoor air temperature / humidity maps for the heating mode in the nonvolatile storage device 23c for each combination of the target set temperature and the target set humidity. An outside air temperature / humidity map used by the control unit 23 may be selected based on the operation mode, the target set temperature, and the target set humidity.

FIG. 6 is a flowchart showing a flow of control of the air conditioning coil during operation in the cooling mode or the dehumidifying mode. When the cooling operation or the dehumidifying operation is started via the remote controller 25, the control unit 23 starts the operation of the air conditioning ventilator in the cooling mode or the dehumidifying mode (step S1). Control unit 23 performs an initial determination of the area from the measurement result of external temperature and humidity sensor 2 8, to operate the air-conditioning coil 7 in cooling capacity values corresponding to the area corresponding to the outside temperature and humidity. For example, if the outside air temperature humidity corresponds to the region (2), the air conditioning coil 7 is operated with a cooling capacity of 75%. However, when it corresponds to the region (5) or the region (6), the air conditioning coil 7 is thermo-off because it is not in the cooling operation possible range (step S2). Thereafter, the control unit 23 determines whether t1 time has elapsed after performing the control in step S2 (step S3). If the time t1 has not elapsed (step S3 / No), the control unit 23 repeats the determination of whether the time t1 has elapsed since the control in step S2 was performed (step S3).

  When t1 time has passed since the control of step S2 (step S3 / Yes), the control unit 23 causes the air-conditioning ventilator to shift from the initial state to the steady state.

  After the transition to the steady state, the control unit 23 stores the region at the time when the time t1 has elapsed and the target superheat degree on the refrigeration cycle that becomes the cooling capacity (step S4). The control unit 23 controls the air conditioning coil 7 aiming at the stored target superheat degree. The control unit 23 determines whether or not the outside air temperature / humidity has changed and changed from the current region to another region, in other words, whether or not the outside air temperature / humidity has exceeded the boundary on the outside air temperature / humidity map (step S5). ). When the outside air temperature / humidity does not exceed the boundary on the outside air temperature / humidity map (step S5 / No), the control unit 23 maintains the cooling capacity in the current region.

  When the outside air temperature / humidity exceeds the boundary on the outside air temperature / humidity map (step S5 / Yes), the timer for measuring the time t2 is turned on (step S6). The timer that measures the time t2 prevents the chattering of the thermo-on-off due to the change in the outside air temperature / humidity around the boundary, the target superheat degree on the refrigeration cycle due to the area change, and the electronic expansion valve opening degree The purpose is to avoid the refrigeration cycle becoming unstable due to a large change. The control unit 23 determines whether t2 hours have elapsed after the timer is turned on (step S7). If the time t2 has not elapsed (step S7 / No), the control unit 23 repeats the determination of whether the time t2 has elapsed since the timer was turned on (step S7).

  When t2 time has elapsed since the timer was turned on (step S7 / Yes), the control unit 23 confirms whether the blowing limiter function is set to be valid or invalid (step S8). When the blowing limiter function is set to invalid (step S8 / invalid), the control unit 23 changes the area and the cooling capacity, and clears the timer (step S9). Thereafter, the process returns to step S4 in which the region immediately after the elapse of t2 and the cooling capacity are stored.

  If the blowout limiter function is set to be valid (step S8 / valid), the blowout limiter function is executed (step S10). The controller 23 performs the process of step S9 after step S10.

FIG. 7 is a flowchart showing a flow of the operation of the blowing limiter function. The control unit 23 predicts the inlet air state of the air conditioning coil 7 from the total heat exchange efficiency of the heat exchanger 3 obtained by measurement in advance and the measured values of the indoor temperature / humidity sensor 29 and the outside air temperature / humidity sensor 28. Further, the control unit 23 performs air conditioning based on the sensible heat exchange efficiency of the air conditioning coil 7 obtained by measurement based on the target superheat degree of the refrigeration cycle, the measured value of the liquid pipe temperature sensor 11, and the inlet air state of the air conditioning coil 7. The outlet temperature of the coil 7, that is, the supply air blowing temperature is predicted. The control unit 23 compares the predicted supply air temperature of the air-conditioning ventilator thus predicted with the indoor supply target temperature preset by the control unit 23 (step S101). When the relationship of the predicted supply air temperature <the indoor supply air target temperature is satisfied due to the excessive decrease in the discharge temperature (step S101 / Yes), the control unit 23 causes condensation on the surface of the indoor outlet provided on the indoor ceiling or the like. As a preventive measure, the air conditioning coil 7 is forcibly thermo-off (step S102). And the control part 23 operates a timer (step S103). The controller 23 determines whether t3 time has elapsed since the timer was activated (step S104). If t3 time has not elapsed (step S104 / No), the controller 23 repeats the determination of whether t3 time has elapsed since the timer was activated (step S104). When t3 time has passed since the timer was operated (step S104 / Yes), the control unit 23 compares the predicted supply air temperature and the indoor supply target temperature (step S101).

  At this time, since the refrigerant does not flow through the air conditioning coil 7 and is in the thermo-off state, the total heat exchange efficiency of the heat exchanger 3 and the indoor temperature / humidity sensor 29 and the outside temperature / humidity sensor 28 which are obtained by measurement in advance are determined. It is used as a predicted value for the supply air temperature of the air-conditioning ventilator from the measured value.

  When the relationship of the predicted supply air temperature <the indoor supply air target temperature is not satisfied (step S101 / No), since there is no concern about condensation, the control unit 23 ends the operation as the discharge limiter function.

  When the operation of the blowing limiter function ends, the process proceeds to step S9.

  In the conventional air-conditioning ventilator, even if the outside air is cold, if the target temperature is set low, the dehumidifying operation can be performed. For example, if the cooling capacity of the air conditioning coil is 100%, the air conditioning coil refrigerant flows when the outside air temperature is low and the dehumidification load due to the absolute humidity difference between the indoor and outdoor air is small, and the dehumidification is performed more than necessary. The temperature of the air after dehumidification falls. When the air is blown into the room as it is, if the supply air temperature from the air conditioning ventilator is lower than the dew point temperature of the indoor environment, the blowout grill provided on the ceiling surface etc. is cooled by the supply air, and the surface of the blowout grille There was a problem that condensation would occur.

On the other hand, according to the embodiment, by controlling the air-conditioning ventilator with a blow-off temperature limiter function, the blow-off temperature from the air-conditioning ventilator does not decrease too much even when the outside air is at low temperature and low humidity, and the ceiling surface It is possible to suppress the dew condensation on the surface of the blowing grill provided in the area and the cold air feeling from the blowing grill. The air-conditioning coil 7 is thermo-off early, and indoor leakage due to condensation can be avoided.

  In the above control, even if the measured value of the outside air temperature / humidity sensor 28 changes and deviates from the region determined in step S2 until t1 has elapsed since the control in step S2, the cooling capacity value is changed or Since thermo-on / off is not performed, sensor measurement errors with respect to the temperature and humidity of the air flow flowing during the initial operation can be reduced, and instability of the start-up of the refrigeration cycle can be eliminated.

  The preset indoor air supply target temperature can be changed in multiple stages by the control unit 23 or the remote controller 25. For example, it can be changed in three stages by selecting high, medium or low with the control unit 23 or the remote controller 25.

By performing the control as described above, heat exchange is performed between the supply air and the exhaust, and the indoor air and the outdoor air are ventilated by simultaneous supply and exhaust while the supply air is cooled by the air conditioning coil 7 and dehumidified. The air-conditioning ventilator can be operated more comfortably and with less energy than in the conventional control. In other words, dehumidifying operation according to the dehumidifying load due to the absolute humidity difference between the inside and outside of the room is possible, preventing unnecessary cooling by the air conditioning coil 7 , preventing the temperature of the air conditioning ventilator from dropping too much, and providing energy-saving and comfortable ventilation. Yes.

  According to the embodiment, when the dehumidification load is small with respect to the dehumidification load due to the absolute humidity difference between the indoor and outdoor air, the outside air temperature and the outside air humidity, which are measured values of the outside air temperature / humidity sensor, are set to the thermo on / off of the air conditioning coil and the target. By using it for the determination of the cooling capacity, the dehumidifying operation can be performed with the cooling capacity of the air conditioning coil reduced more than when it is 100%. As a result, the supply air is blown out from the air-conditioning ventilator in an air state that is equal to or lower than the preset indoor absolute humidity, and unnecessary dehumidification is eliminated. Therefore, the cooling load of the other air conditioner installed in the room is reduced, and the energy saving operation can be performed as the whole system.

  Further, according to the embodiment, by setting the indoor temperature and the indoor absolute humidity set in advance to be equal to or higher than the reference value, the dehumidifying load becomes smaller than when the reference value is set, and the air conditioning based on the measured value of the outside air temperature / humidity sensor The target cooling capacity range in which the coil is thermo-ON moves to the high temperature side of the outside air temperature, and conversely, the region where the air conditioning coil is thermo-off increases on the low temperature side of the outside air temperature. Therefore, the compressor built in the heat source unit stops, the power consumption for the heat source unit can be reduced, and the entire system can perform energy saving operation.

  In addition, according to the embodiment, it is possible to reduce the indoor sensible heat load without operating the heat source unit by using the low temperature and low humidity outside air when the air conditioning coil is thermo-off. Even if the simultaneous supply and exhaust ventilation is continued, the absolute humidity in the room is lowered and uncomfortable feeling is unlikely to occur.

  In addition, according to the embodiment, since the indoor dew point temperature is obtained from the measured value of the indoor temperature / humidity sensor disposed in the casing, the air conditioning ventilation is performed according to the surrounding environment in which the air conditioning ventilation apparatus is installed. It is possible for the device to automatically determine the blowout limiter temperature.

  In addition, according to the embodiment, it is possible to select whether priority is given to the removal of the sensible heat load or priority to the removal of the latent heat load by the air conditioning coil according to the use application and the use environment.

  As described above, according to the present embodiment, the heat exchanger that is installed between the supply air passage and the exhaust air passage and performs heat exchange between the supply air and the exhaust air flow, and the heat exchange of the supply air passage An air conditioning coil that is installed on the downstream side of the heat exchanger and whose cooling capacity for the supply air after heat exchange can be changed in multiple stages, an outside air temperature / humidity sensor that measures the temperature and humidity of the outside air, and the outside air temperature and relative For each combination with humidity, store reference data that defines the cooling capacity so that the absolute humidity of the air supplied to the room is below the indoor target absolute humidity, and based on the measurement results and reference data of the outside air temperature and humidity sensor Since it has a control unit for determining the cooling capacity value of the air conditioning coil, when it is not necessary to operate the air conditioning coil at 100% during the cooling operation, it is possible to perform the energy saving operation by suppressing the capacity of the air conditioning coil. .

  As described above, the air-conditioning ventilator according to the present invention is useful in that it can perform the dehumidifying operation by the air-conditioning coil with the capacity required, and particularly, it is used in combination with other air conditioners to constitute the air-conditioning system. Suitable for

  DESCRIPTION OF SYMBOLS 1 Exhaust air blower, 2 Exhaust ventilation path, 3 Heat exchanger, 4 Damper, 5 Casing, 6 Supply air blower, 7 Air-conditioning coil, 8 Humidifier, 9 Indoor air intake path, 10 Indoor air inlet, 11 Liquid pipe Temperature sensor, 12 Indoor air outlet, 13 Outdoor air outlet, 14 Outdoor air inlet, 15 Outdoor air intake passage, 16 Maintenance cover, 17 Air supply air passage, 18 Exhaust flow, 19 Gas pipe temperature sensor, 20 Electron Expansion valve, 21 Bypass air passage, 22 Air supply, 23 Control unit, 24 Heat source unit, 25 Remote controller, 26 Refrigerant piping, 27 Humidification air passage, 28 Outside air temperature / humidity sensor, 29 Indoor temperature / humidity sensor, 30 Exhaust passage, 31 Air supply passage, 32 Lower part of humidification air passage, 33 Upper part of humidification air passage, 50 Air conditioning ventilator.

Claims (6)

An air-conditioning ventilator that exhausts indoor air to the outside, adjusts the outdoor air to a preset indoor target temperature and indoor target absolute humidity, and supplies the indoor air.
A casing having an air supply air passage connecting the outdoor air inlet and the indoor air outlet, and an exhaust air passage connecting the indoor air inlet and the outdoor air outlet,
An air supply blower that is installed on the air supply air passage, sucks the outside air from the outdoor-side intake port, and supplies the indoor air from the indoor-side air outlet;
An exhaust blower that is installed on the exhaust air passage, sucks the room air from the indoor side air inlet, and exhausts the air from the outdoor side air outlet to the outside;
A heat exchanger that is installed between the supply air passage and the exhaust air passage, and performs heat exchange between the supply air and the exhaust;
An air conditioning coil that is installed on the downstream side of the heat exchanger of the air supply air passage, and the cooling capacity for the outside air after heat exchange can be changed in multiple stages,
An outside air humidity sensor for measuring the temperature and relative humidity of the outside air;
For each combination of the temperature and relative humidity of the outside air, the cooling capacity is determined based on a dehumidifying load corresponding to an absolute humidity difference between the inside and outside of the room so that the absolute humidity of the supply air is equal to or less than the indoor target absolute humidity. A control unit that stores the reference data and determines the cooling capacity value of the air conditioning coil based on the measurement result of the outside air temperature and humidity sensor and the reference data during cooling operation,
Refrigerant flow rate adjusting means for adjusting the flow rate of the refrigerant flowing through the air conditioning coil;
A refrigerant temperature sensor for measuring the temperature of the refrigerant flowing in the air conditioning coil,
The control unit calculates an actual superheat degree of the refrigerant based on a measurement result of the refrigerant temperature sensor,
The control unit controls the refrigerant flow rate adjusting unit so that the actual superheat degree of the refrigerant becomes a target superheat degree corresponding to the cooling capacity determined based on the reference data. . The indoor target temperature and the indoor target absolute humidity can be selected and set from a plurality of combinations,
The air conditioning ventilator according to claim 1, wherein the control unit has the reference data for each combination of the indoor target temperature and the indoor target absolute humidity. A bypass air passage that guides the room air from the indoor air inlet to the outdoor air outlet without passing through the heat exchanger;
A damper that switches between the exhaust air passage and the bypass air passage;
The controller is
A first humidity correction value, a second humidity correction value smaller than the first humidity correction value, a third humidity correction value smaller than the second humidity correction value, and a temperature correction value are stored. And
When the absolute humidity of the outside air after heat exchange in the heat exchanger is higher than the indoor target absolute humidity by the first humidity correction value or more, the target superheat degree is set as the first target superheat degree,
When the absolute humidity of the outside air after heat exchange in the heat exchanger is higher than the indoor target absolute humidity by the second humidity correction value or more, the target superheat degree is set higher than the first target superheat degree. Is the second target superheat degree,
When the absolute humidity of the outside air after heat exchange in the heat exchanger is higher than the indoor target absolute humidity by the third humidity correction value or more, the target superheat degree is set higher than the second target superheat degree. Is the third target superheat degree,
When the absolute humidity of the outdoor air after heat exchange in the heat exchanger is lower than the indoor target absolute humidity and the temperature of the outdoor air is lower than the indoor target temperature by the temperature correction value or more, Thermo-off the air conditioning coil and control the damper so that the room air passes through the bypass air passage,
When the absolute humidity of the outdoor air after heat exchange in the heat exchanger is lower than the indoor target absolute humidity and the temperature of the outdoor air is higher than the indoor target temperature below the temperature correction value, The air conditioning ventilator according to claim 1 or 2 , wherein the air conditioning coil is thermo-offed and the damper is controlled so that the room air passes through the exhaust air passage. An indoor temperature / humidity sensor for measuring the temperature and relative humidity of the room air;
Have
The controller is
Based on the temperature and relative humidity of the outside air measured by the outside temperature and humidity sensor, the temperature and relative humidity of the room air measured by the room temperature and humidity sensor, and the temperature of the refrigerant measured by the refrigerant temperature sensor, Predict the temperature of the supply air,
When the predicted value of the temperature of the supply air is lower than the indoor target temperature, the cooling by the air conditioning coil is stopped and the air blowing operation is performed.
The cooling stop by the air conditioning coil is canceled when the predicted value of the temperature of the supply air is equal to or higher than a threshold temperature after the preset time has elapsed since the cooling by the air conditioning coil is stopped. The air-conditioning ventilator according to claim 3 . The air conditioning ventilator according to claim 4 , wherein the indoor target temperature is an indoor dew point temperature. Whether or not to compare the indoor target temperature with the predicted value of the supply air temperature can be set, and in the case where the comparison is not performed, the humidity of the indoor air measured by the indoor temperature and humidity sensor The air-conditioning ventilator according to claim 4 or 5 , wherein the dehumidifying operation by the air-conditioning coil is continued until the indoor target absolute humidity is reached.

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